Trying to wean my 11 month old from feeding?

I'm slowly trying to wean my 11 month old from the but am having such a hard time cause he screams and hollers until he gets it . I have been pumping milk and giving it to him in his sippy cup but at night he must have it I get beat on my chest pulls my hair until he gets it, sometimes even in public (at a friends or family members house) he would even pull down my shirt to try to nurse ( that's why I feel like its time to stop nursing him) . I love nursing him its ow er lil quiet time together but i think its time for it to stop, plus am trying to go back to work by the time he turns 1 yrs old . I just need some ideas ppl . ( I also thought about even waiting until he was ready to stop nursing on his own )